//
//  Blitter.hpp
//  Clock Signal
//
//  Created by Thomas Harte on 22/07/2021.
//  Copyright © 2021 Thomas Harte. All rights reserved.
//

#pragma once

#include <cstddef>
#include <cstdint>
#include <string>
#include <vector>

#include "ClockReceiver/ClockReceiver.hpp"
#include "BlitterSequencer.hpp"
#include "DMADevice.hpp"

namespace Amiga {

/*!
	If @c record_bus is @c true then all bus interactions will be recorded
	and can subsequently be retrieved. This is included for testing purposes.
*/
template <bool record_bus = false> class Blitter: public DMADevice<4, 4> {
public:
	using DMADevice::DMADevice;

	template <int id, int shift> void set_pointer(uint16_t value) {
		DMADevice<4, 4>::set_pointer<id, shift>(value);
	}

	// Various setters; it's assumed that address decoding is handled externally.
	//
	// In all cases where a channel is identified numerically, it's taken that
	// 0 = A, 1 = B, 2 = C, 3 = D.
	void set_control(int index, uint16_t value);
	void set_first_word_mask(uint16_t value);
	void set_last_word_mask(uint16_t value);

	void set_size(uint16_t value);
	void set_minterms(uint16_t value);
//	void set_vertical_size(uint16_t value);
//	void set_horizontal_size(uint16_t value);
	void set_data(int channel, uint16_t value);

	uint16_t get_status();

	template <bool complete_immediately> bool advance_dma();

	struct Transaction {
		enum class Type {
			SkippedSlot,
			ReadA,
			ReadB,
			ReadC,
			AddToPipeline,
			WriteFromPipeline
		} type = Type::SkippedSlot;

		uint32_t address = 0;
		uint16_t value = 0;

		Transaction() = default;
		Transaction(Type type) : type(type) {}
		Transaction(Type type, uint32_t address, uint16_t value) : type(type), address(address), value(value) {}

		std::string to_string() const {
			std::string result;

			switch(type) {
				case Type::SkippedSlot:			result = "SkippedSlot";			break;
				case Type::ReadA:				result = "ReadA";				break;
				case Type::ReadB:				result = "ReadB";				break;
				case Type::ReadC:				result = "ReadC";				break;
				case Type::AddToPipeline:		result = "AddToPipeline";		break;
				case Type::WriteFromPipeline:	result = "WriteFromPipeline";	break;
			}

			result += " address:" + std::to_string(address) + " value:" + std::to_string(value);
			return result;
		}
	};
	std::vector<Transaction> get_and_reset_transactions();

private:
	int width_ = 0, height_ = 0;
	int shifts_[2]{};
	uint16_t a_mask_[2] = {0xffff, 0xffff};

	bool line_mode_ = false;
	bool one_dot_ = false;
	int line_direction_ = 0;
	int line_sign_ = 1;

	uint32_t direction_ = 1;
	bool inclusive_fill_ = false;
	bool exclusive_fill_ = false;
	bool fill_carry_ = false;

	uint8_t minterms_ = 0;
	uint32_t a32_ = 0, b32_ = 0;
	uint16_t a_data_ = 0, b_data_ = 0, c_data_ = 0;

	bool not_zero_flag_ = false;

	BlitterSequencer sequencer_;
	uint32_t write_address_ = 0xffff'ffff;
	uint16_t write_value_ = 0;
	enum WritePhase {
		Starting, Full
	} write_phase_;
	int y_, x_;
	uint16_t transient_a_mask_;
	bool busy_ = false;
	int loop_index_ = -1;

	int error_ = 0;
	bool draw_ = false;
	bool has_c_data_ = false;

	void add_modulos();
	std::vector<Transaction> transactions_;
};

}
